Network address functions and operators - PolarDB - Alibaba Cloud Documentation Center

This topic describes the network address functions and operators supported by.

The IP network address types,cidr and inet, support the usual comparison operators as well as the specialized operators and functions.

Any cidr value can be cast to inet implicitly; therefore, the operators and functions shown below as operating on inet also work on cidr values. (Where there are separate functions for inet and cidr, it is because the behavior should be different for the two cases.) Also, it is permitted to cast an inet value to cidr. When this is done, any bits to the right of the netmask are silently zeroed to create a valid cidr value.

IP address operators

inet << inet→boolean

Is subnet strictly contained by subnet? This operator, and the next four, test for subnet inclusion. They consider only the network parts of the two addresses (ignoring any bits to the right of the netmasks) and determine whether one network is identical to or a subnet of the other.

inet '192.168.1.5' << inet '192.168.1/24'→t

inet '192.168.0.5' << inet '192.168.1/24'→f

inet '192.168.1/24' << inet '192.168.1/24'→f

inet <<= inet→boolean

Is subnet contained by or equal to subnet?

inet '192.168.1/24' <<= inet '192.168.1/24'→t

inet >> inet→boolean

Does subnet strictly contain subnet?

inet '192.168.1/24' >> inet '192.168.1.5'→t

inet >>= inet→boolean

Does subnet contain or equal subnet?

inet '192.168.1/24' >>= inet '192.168.1/24'→t

inet && inet→boolean

Does either subnet contain or equal the other?

inet '192.168.1/24' && inet '192.168.1.80/28'→t

inet '192.168.1/24' && inet '192.168.2.0/28'→f

~ inet→inet

Computes bitwise NOT.

~ inet '192.168.1.6'→63.87.254.249

inet & inet→inet

Computes bitwise AND.

inet '192.168.1.6' & inet '0.0.0.255'→0.0.0.6

inet | inet→inet

Computes bitwise OR.

inet '192.168.1.6' | inet '0.0.0.255'→192.168.1.255

inet + bigint→inet

Adds an offset to an address.

inet '192.168.1.6' + 25→192.168.1.31

bigint + inet→inet

Adds an offset to an address.

200 + inet '::ffff:fff0:1'→::ffff:255.240.0.201

inet - bigint→inet

Subtracts an offset from an address.

inet '192.168.1.43' - 36→192.168.1.7

inet - inet→bigint

Computes the difference of two addresses.

inet '192.168.1.43' - inet '192.168.1.19'→24

inet '::1' - inet '::ffff:1'→-4294901760

IP address functions

abbrev(inet) →text

Creates an abbreviated display format as text. (The result is the same as the inet output function produces; it is“abbreviated”only in comparison to the result of an explicit cast to text, which for historical reasons will never suppress the netmask part.)

abbrev(inet '10.1.0.0/32')→10.1.0.0

abbrev(cidr) →text

Creates an abbreviated display format as text. (The abbreviation consists of dropping all-zero octets to the right of the netmask.)

abbrev(cidr '10.1.0.0/16')→10.1/16

broadcast(inet) →inet

Computes the broadcast address for the address's network.

broadcast(inet '192.168.1.5/24')→192.168.1.255/24

family(inet) →integer

Returns the address's family:4 for IPv4,6 for IPv6.

family(inet '::1')→6

host(inet) →text

Returns the IP address as text, ignoring the netmask.

host(inet '192.168.1.0/24')→192.168.1.0

hostmask(inet) →inet

Computes the host mask for the address's network.

hostmask(inet '192.168.23.20/30')→0.0.0.3

inet_merge(inet,inet) →cidr

Computes the smallest network that includes both of the given networks.

inet_merge(inet '192.168.1.5/24', inet '192.168.2.5/24')→192.168.0.0/22

inet_same_family(inet,inet) →boolean

Tests whether the addresses belong to the same IP family.

inet_same_family(inet '192.168.1.5/24', inet '::1')→f

masklen(inet) →integer

Returns the netmask length in bits.

masklen(inet '192.168.1.5/24')→24

netmask(inet) →inet

Computes the network mask for the address's network.

netmask(inet '192.168.1.5/24')→255.255.255.0

network(inet) →cidr

Returns the network part of the address, zeroing out whatever is to the right of the netmask. (This is equivalent to casting the value to cidr.)

network(inet '192.168.1.5/24')→192.168.1.0/24

set_masklen(inet,integer) →inet

Sets the netmask length for an inet value. The address part does not change.

set_masklen(inet '192.168.1.5/24', 16)→192.168.1.5/16

set_masklen(cidr,integer) →cidr

Sets the netmask length for a cidr value. Address bits to the right of the new netmask are set to zero.

set_masklen(cidr '192.168.1.0/24', 16)→192.168.0.0/16

text(inet) →text

Returns the unabbreviated IP address and netmask length as text. (This has the same result as an explicit cast to text.)

text(inet '192.168.1.5')→192.168.1.5/32

Note

The abbrev,host, and text functions are primarily intended to offer alternative display formats for IP addresses.

The MAC address types,macaddr and macaddr8, support the usual comparison operators as well as the specialized functions. In addition, they support the bitwise logical operators ~,& and |(NOT, AND and OR), just as shown above for IP addresses.

MAC address functions

trunc(macaddr) →macaddr

Sets the last 3 bytes of the address to zero. The remaining prefix can be associated with a particular manufacturer (using data not included inPostgreSQL).

trunc(macaddr '12:34:56:78:90:ab')→12:34:56:00:00:00

trunc(macaddr8) →macaddr8

Sets the last 5 bytes of the address to zero. The remaining prefix can be associated with a particular manufacturer (using data not included inPostgreSQL).

trunc(macaddr8 '12:34:56:78:90:ab:cd:ef')→12:34:56:00:00:00:00:00

macaddr8_set7bit(macaddr8) →macaddr8

Sets the 7th bit of the address to one, creating what is known as modified EUI-64, for inclusion in an IPv6 address.

macaddr8_set7bit(macaddr8 '00:34:56:ab:cd:ef')→02:34:56:ff:fe:ab:cd:ef